A comparative study of CVD TiN and CVD TaN diffusion barriers for copper interconnection

In this paper, the barrier properties of metalorganic CVD TiN and CVD TaN between Cu and Si under similar process conditions are compared. Thermal stability was investigated by microstructural analysis and junction diode leakage current. Results indicate that CVD TiN and CVD TaN films have comparable thermal stability. A post-deposition treatment using rapid thermal annealing in ammonia at temperatures greater than 600/spl deg/C was found to improve the thermal stability and to lower the film resistivity.